SYDNEY (Reuters) - The euro flirted with 11-year lows early on Monday as investors braced for the European Central Bank to take its boldest steps yet to combat deflation and revive the euro zone economy.

The common currency last traded at US$1.1561, not far from a trough of US$1.14595 hit on Friday. Against the yen, it fetched 135.71, near a three-month low of 134.70.

That the ECB will launch a large-scale sovereign bond-buying program at its Jan. 22 meeting is no longer in question, but what is unknown is how the plan will be designed and whether it will be seen as credible and sufficient.

"There will no doubt be a lot of wire traffic after Thursday's meeting about these details and such structural shortcomings, but the total QE to be announced will get prime attention," said David de Garis, senior economist at National Australia Bank, adding the market was now looking for quantitative easing of 1 trillion euros.

The common currency struggled near a four-month trough against the Australian dollar and a record low on the New Zealand currency. On the Canadian dollar, the euro remained within reach of a 16-month trough of C$1.3749 set on Friday.

Pressure on the euro intensified last week after the Swiss National Bank shocked markets by abandoning its three-year-old currency cap, effective removing a pillar of support for the euro.

The SNB had been buying billions of euros in order to keep the franc from strengthening above the 1.20 per euro cap it had implemented back in September 2011.

The abrupt policy U-turn sparked speculation the SNB was forced to do so ahead of bold moves from the ECB. The Swiss franc rocketed across the board, although it seemed to have stabilised around 0.99365 francs per euro.

Further stirring expectations for imminent action, media reports suggested ECB President Mario Draghi met with German Chancellor Angela Merkel last week to smooth the path for quantitative easing, which is staunchly opposed by the Bundesbank.

Whatever the outcome, traders said there is sure to be plenty of volatility at the end of this week.

But for now, with the U.S. markets shut on Monday for a public holiday and little in the way of market-moving economic data, currency markets could be in for a relatively slow session.

On Tuesday, investors will get an update on China's fourth-quarter growth numbers.